1. Field
The present general inventive concept relates to electronic avionics systems and methods, more particularly, the present general inventive concept relates to systems and methods to detect and/or provide backup in the event of failures, obstructions, or improper operation of an aircraft pitot pressure sensing system or other failures of instruments. In one embodiment, the present general inventive concept relates to a unique electronic flight display architecture that meets the FAR 23.1311(b) regulatory requirement for redundant backup instruments in the cockpit. In another embodiment the general inventive concept uses a combination of dissimilar sensor data and displays information to an avionics display.
2. Description of Related Art
The FAA Advisory Circular 23.1311-1B sets forth acceptable means of showing compliance with 14 CFR §23 for installing electronic displays in part 23 airplanes. Among other things, it requires a reversionary or backup architecture for electronic primary flight displays, or an equivalent level of safety.
Pitot pressure and ambient static pressure are used to determine aircraft indicated airspeed, which is a critical performance determinant of the aircraft and which is also often used to schedule the performance or operation of various aircraft systems, e.g., trim motors, artificial feel systems, envelope protection systems, or may be used in the computation of other flight parameters, e.g., attitude information from an Air Data Attitude Heading Reference System (ADAHRS).
Where failure of the pitot system is a critical failure, conventional aircraft design implements a pitot sensing architecture with sufficient redundancy to assure availability of reliable data. Examples of such redundancy architectures are dual redundant pitot probes with dual redundant and monitored heating elements, with each probe heater connected to a different power generation source. In many legacy light aircraft, the installed pitot system does not possess sufficient redundancy to assure availability of the accurate data, which can result in use of misleading data and/or which generally precludes the use of data in performing critical functions, and retrofitting such legacy aircraft with redundant pitot systems is extremely difficult and costly.